Removing the Rear Torsion Bar inside the Aspire Rear Beam

[Doug Brown]

Hard way: Step drill it out to 13/16-inch. Takes about 2-hours depending how sharp your drill bits are.

Easy way: Use a 7/8" to 1-1/4" Bi-Metal hole saw. Takes 2-MINUTES!

In both cases a 1/2" drill motor works well, smear grease on the drill bits and the area to be drilled.

Enlarge the hole in the end of the torsion bar to 1/4" and drill it deeper into the torsion bar. This is so the pilot drill on the hole saw can easily guide the hole saw instead of it having to drill a hole.

You will need to remove both rims, but it can be drilled out with the rear beam still attached to the car.

Picture shows location of torsion bar and the hole left after the bar has been drilled out. LOTS of metal still in the area!

There are articles by Advanced Dynamics about the handling benefits you get by removing the torsion bar. I did it for weight savings since I'm building a drag racer.

[Dragonhealer]

You must be a bear wrestler, the hole saw method works well, but it took me 40 minutes :O
Should have used a larger than one inch hole saw....

[Doug Brown]

I did - I used a 1-3/8" one and all it had to cut thru was sheet metal (about 1/8" thick) and no welds. Using regular drill bits was a real nightmare because you were cutting into solid metal (the torsion bar) instead of sheet metal.

Once I made the hole saw cut and looked things over, I think anything in the 1 to 1-1/8" size would have worked out OK.

I think part of the secret was using the 1/2" drill motor which turns at a slower rpm and greasing up the hole saw and the area to be cut.

Lubrication is good.....

Drilling it out while the rear beam is still on the car would take care of the problem of "how do I hold this thing?" when drilling!

[Dragonhealer]

Yes, feed rate, RPM and proper lube are important, but I was cutting a fair amount of weld with the 1 inch saw. May be a fair bit of variation in welds. I wasn't smart enough to mount the beam first!

[bhazard]

I kinda wanna try an autocross before I cut mine out just to see how much the car rotates with it.